JP2923494B1 - Treatment method for dioxin-containing wastewater - Google Patents
Treatment method for dioxin-containing wastewaterInfo
- Publication number
- JP2923494B1 JP2923494B1 JP8060798A JP8060798A JP2923494B1 JP 2923494 B1 JP2923494 B1 JP 2923494B1 JP 8060798 A JP8060798 A JP 8060798A JP 8060798 A JP8060798 A JP 8060798A JP 2923494 B1 JP2923494 B1 JP 2923494B1
- Authority
- JP
- Japan
- Prior art keywords
- dioxin
- wastewater
- manganese dioxide
- ozone
- dioxide catalyst
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
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- Treatment Of Water By Oxidation Or Reduction (AREA)
- Catalysts (AREA)
- Removal Of Specific Substances (AREA)
Abstract
【要約】
【課題】排水中のダイオキシンその他の有機塩素化合物
化合物を、効果的にかつ経済的に分解除去する方法を提
供する。
【解決手段】第1の発明では、ダイオキシンその他の有
機塩素化合物化合物を含有する排水を、二酸化マンガン
触媒を充填した反応塔1に通水することにより、排水中
の有機塩素化合物化合物から塩素を脱離させる。第2の
発明では、二酸化マンガン触媒を充填した反応塔にオゾ
ンを供給し、有機塩素化合物化合物を分解除去する。二
酸化マンガン触媒は粉末、粒状あるいはセラミックス等
の無機材料や高分子樹脂等の有機材料に担持させた形状
で用いることが好ましい。A method for effectively and economically decomposing and removing dioxin and other organochlorine compounds in wastewater is provided. According to a first aspect of the present invention, a wastewater containing dioxin and other organic chlorine compound is passed through a reaction tower 1 filled with a manganese dioxide catalyst to remove chlorine from the organic chlorine compound in the wastewater. Let go. In the second invention, ozone is supplied to a reaction tower filled with a manganese dioxide catalyst to decompose and remove the organochlorine compound. The manganese dioxide catalyst is preferably used in the form of powder, granules, or a form supported on an inorganic material such as ceramics or an organic material such as a polymer resin.
Description
【0001】[0001]
【発明の属する技術分野】本発明は、下水二次処理水、
ごみ埋立地の浸出水、河川、し尿、産業排水などの排水
中から、ダイオキシンを効率よく除去することができる
ダイオキシン含有排水の処理方法に関するものである。TECHNICAL FIELD The present invention relates to secondary sewage water,
Landfill leachate, rivers, human waste, from the waste water, such as industrial waste water, it is possible to efficiently remove dioxin
The present invention relates to a method for treating dioxin- containing wastewater.
【0002】[0002]
【従来の技術】排水中から効果的にダイオキシンを除去
する手段として、ダイオキシンが水への溶解度が小さい
こと及び汚泥に吸着されやすいことから、砂ろ過法や凝
集沈殿法によりSSとともに除去する方法が知られてい
る。更に、紫外線とオゾンを組み合わせた酸化分解処理
法も知られている。As a means to effectively remove dioxins BACKGROUND OF THE INVENTION wastewater, a method of removing from the dioxin tends to be adsorbed to and sludge solubility in water is small, with SS by sand filtration method or flocculation precipitation method It has been known. Further, an oxidative decomposition treatment method using a combination of ultraviolet light and ozone is also known.
【0003】しかし、砂ろ過法、凝集沈殿法では一部の
溶解性のダイオキシン類は除去されずに処理水中に残留
する。更に紫外線とオゾンを組み合わせた酸化分解処理
法は排水中のダイオキシンを分解除去する効果に優れて
いるが、紫外線照射による処理コストが高くなってしま
う問題点がある。However , in the sand filtration method and the coagulation sedimentation method, some soluble dioxins are not removed but remain in the treated water. Further, the oxidative decomposition treatment method using a combination of ultraviolet light and ozone is excellent in the effect of decomposing and removing dioxin in wastewater, but has a problem that the treatment cost by irradiation with ultraviolet light is increased.
【0004】[0004]
【発明が解決しようとする課題】本発明は上記した従来
の問題点を解消し、排水中のダイオキシンその他の有機
塩素化合物化合物を、効果的にかつ経済的に分解除去す
ることができる有機塩素化合物含有排水の処理方法を提
供するためになされたものである。SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and provides an organic chlorine compound capable of effectively and economically decomposing and removing dioxin and other organic chlorine compound compounds in wastewater. The purpose of the present invention is to provide a method for treating contained wastewater.
【0005】[0005]
【課題を解決するための手段】上記の課題を解決するた
めになされた本発明のダイオキシン含有排水の処理方法
は、ダイオキシンを含有する排水を 粉末、粒状の二酸
化マンガン触媒を充填した反応塔に通水しつつ、排水中
に共存するCODの3倍(重量比)以上のオゾンを供給
することにより、排水中の高塩素数のダイオキシンのみ
ならず低塩素数のダイオキシンから塩素を脱離分解させ
ることを特徴とするものである。またセラミックス等の
無機材料や高分子樹脂等の有機材料に担持させた形状の
二酸化マンガン触媒を用いることが好ましい。 Dioxin-containing waste water of the present invention has been made in order to solve the above problems, there is provided a means for solving processing method <br/> the powder waste water containing dioxins, diacid particulate <br/> While passing water through a reaction tower filled with a manganese oxide catalyst ,
By supplying ozone more than 3 times (weight ratio) of COD coexisting in water, only dioxin with high chlorine number in wastewater
In addition, it is characterized in that chlorine is eliminated and decomposed from dioxin having a low chlorine number . Further, it is preferable to use a manganese dioxide catalyst in a shape supported by an inorganic material such as ceramics or an organic material such as a polymer resin.
【0006】本発明では、排水を高塩素数のダイオキシ
ンから塩素を脱離させる効果のある二酸化マンガン触媒
と接触させるときに排水中に共存するCODの3倍(重
量比)以上のオゾンを供給することにより、排水中の高
塩素数のダイオキシンのみならず低塩素数のダイオキシ
ンにつても低減させることができる。この二酸化マンガ
ン触媒は脱塩素効果のほかにオゾンを分解し、酸化分解
に効果的なラジカル種を生成させるので、低塩素数のダ
イオキシンの分解除去を促進させることができる。この
処理法は紫外線オゾン処理法と比較して高効率で安価に
行うことができる。[0006] In the present invention, the wastewater is treated with high chlorine
3 times the COD coexisting in the waste water when contacted with the manganese dioxide catalyst is effective for the chlorine from the emissions desorbed (heavy
By supplying ratio) or more of ozone, high in the waste water
Not only dioxin with chlorine number but also dioxin with low chlorine number
Can also be reduced. Since manganese dioxide catalyst to decompose the ozone in addition to the dechlorination effect, to produce an effective radical species in oxidation degradation, low chlorine number da
Decomposition and removal of ioxin can be promoted. This processing method can be performed with high efficiency and at low cost as compared with the ultraviolet ozone processing method.
【0007】[0007]
【発明の実施の形態】以下に本発明の好ましい実施形態
を示す。図1は本発明の参考方法を示す図であり、1は
反応槽、2は二酸化マンガン触媒の触媒充填槽である。
この触媒充填層2には、粉末、粒状の二酸化マンガン触
媒、あるいはセラミックス等の無機材料や高分子樹脂等
の有機材料に担持させた形状の二酸化マンガン触媒が充
填されている。ダイオキシンを含有した排水は排水供給
ライン3から反応槽1に供給され、触媒充填層2を通過
する間に二酸化マンガン触媒の酸化力によりダイオキシ
ンから塩素を脱離させ、処理水ライン4から取り出され
る。この結果、排水中のダイオキシン濃度は低減化され
る。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. FIG. 1 is a view showing a reference method of the present invention, wherein 1 is a reaction tank, and 2 is a catalyst filling tank for a manganese dioxide catalyst.
The catalyst-filled layer 2 is filled with a powdered or granular manganese dioxide catalyst, or a manganese dioxide catalyst supported on an inorganic material such as ceramics or an organic material such as a polymer resin. Wastewater containing dioxin is supplied to the reaction vessel 1 from the drain supply line 3, dioxin by oxidizing power of manganese dioxide catalyst while passing through the catalyst-packed layer 2
Desorbed chlorine from emission is taken out from the treated water line 4. As a result, the dioxin concentration in the wastewater is reduced.
【0008】この参考方法の発明は効果的にかつ経済的
に脱塩素処理を行うことができるが、塩素数が低下する
と毒性が高くなるダイオキシンに対しては、却って毒性
を高める恐れがあり好ましくない。[0008] While the invention reference method can be performed effectively and economically dechlorination, for dioxins salts prime is highly toxic when lowered, there is a possibility that rather increase the toxicity undesirable .
【0009】図2は本発明の実施形態を示す図であり、
1は反応槽、2は二酸化マンガン触媒の触媒充填層であ
る。第2の発明では、触媒充填層2の下部にオゾンガス
散気装置5が設けられ、オゾン供給ライン6からオゾン
ガスが供給される。反応槽1の上部は密閉されており、
排オゾンガスは排オゾン処理装置7で分解除去される。
ダイオキシンを含有した排水は排水供給ライン3から反
応槽1に供給され、触媒充填層2を通過する間にオゾン
ガス散気装置5からのオゾンガスと接触する。FIG. 2 is a diagram showing an embodiment of the present invention.
1 is a reaction tank and 2 is a catalyst packed bed of a manganese dioxide catalyst. In the second invention, an ozone gas diffusing device 5 is provided below the catalyst packed layer 2, and ozone gas is supplied from an ozone supply line 6. The upper part of the reaction tank 1 is closed,
The exhaust ozone gas is decomposed and removed by the exhaust ozone treatment device 7.
The wastewater containing dioxin is supplied from the wastewater supply line 3 to the reaction tank 1, and comes into contact with the ozone gas from the ozone gas diffuser 5 while passing through the catalyst packed bed 2.
【0010】オゾンは直接排水中のダイオキシンを分解
するほか、二酸化マンガン触媒の存在下でオゾンよりも
更に酸化力の強いラジカル種を生成し、このラジカル種
がさらに効果的にダイオキシンを分解除去する。このと
きのオゾンの添加量は、共存するCODを目安として、
重量比でCODの3倍以上とすることが望ましい。この
ようにしてダイオキシンが分解除去された処理水は処理
水ライン4から取り出される。この発明によれば、脱塩
素反応に加え、ラジカル種による酸化分解反応によりダ
イオキシンの分解が促進され、参考方法の場合よりもさ
らに強力にダイオキシンの処理が行える。以下にこれら
の発明の実施例を示す。Ozone directly decomposes dioxin in wastewater, and in the presence of a manganese dioxide catalyst, generates radical species having a stronger oxidizing power than ozone, and these radical species decompose and remove dioxin more effectively. The amount of ozone added at this time is based on the coexisting COD,
It is desirable that the weight ratio be at least three times the COD. The treated water from which dioxin has been decomposed and removed in this manner is taken out of the treated water line 4. According to inventions of this, in addition to the dechlorination reaction, da by oxidative decomposition reaction due to radical species
Decomposition of ioxin is promoted, and dioxin can be treated more strongly than in the case of the reference method . Examples of these inventions will be described below.
【0011】[0011]
【実施例】図1の装置の触媒充填層2に、ハニカム状に
成形したセラミック担体に二酸化マンガン触媒を担持さ
せたものを充填し、有機塩素化合物化合物の一種である
ダイオキシン類を含有したごみ埋立地浸出水を、滞留時
間が30分となるよう通水した。この参考方法による原
水及び処理水の各ダイオキシン類の濃度変化を表1に示
した。なお、TEQは毒性等価換算濃度を意味する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The catalyst-filled layer 2 of the apparatus shown in FIG. 1 is filled with a honeycomb-shaped ceramic carrier carrying a manganese dioxide catalyst, and the waste is landfilled containing dioxins, a kind of organochlorine compound. The ground leachate was passed through so that the residence time was 30 minutes. Table 1 shows the change in the concentration of each dioxin in the raw water and the treated water according to this reference method . In addition, TEQ means a concentration equivalent to toxicity.
【0012】[0012]
【表1】 [Table 1]
【0013】この表1に示したように、参考方法では、
排水を二酸化マンガン触媒の充填層に通すことにより、
塩素数が6〜8のダイオキシン類は減少し、60〜70
%の除去率が得られた。一方、塩素数が4のT4CDD
S が増加している。このように二酸化マンガンによる酸
化により、脱塩素反応が起こり塩素数が減少しているの
が分かる。またTEQは17から12へ減少している。As shown in Table 1, in the reference method,
By passing the wastewater through a packed bed of manganese dioxide catalyst,
Dioxins having 6 to 8 chlorine atoms decrease, and 60 to 70
% Removal was obtained. On the other hand, T4CDD with 4 chlorine atoms
S is increasing. Thus, it can be seen that the oxidation with manganese dioxide causes a dechlorination reaction and the chlorine number decreases. Also, the TEQ has decreased from 17 to 12.
【0014】図2の装置の触媒充填層2に、ハニカム状
に成形したセラミック担体に二酸化マンガン触媒を担持
させたものを充填し、CODの5.5倍のオゾンを供給
しつつ、ダイオキシン類を含有したごみ埋立地浸出水を
通水した。滞留時間は30分である。この本発明の実施
例による原水及び処理水の各ダイオキシン類の濃度変化
は表2に示した通りであった。The catalyst-filled layer 2 of the apparatus shown in FIG. 2 is filled with a honeycomb-shaped ceramic carrier carrying a manganese dioxide catalyst, and while supplying 5.5 times the COD of ozone, dioxins are removed. Leachate containing leachate was passed through. The residence time is 30 minutes. Implementation of this invention
Table 2 shows the change in the concentration of each dioxin in the raw water and the treated water according to the example .
【0015】[0015]
【表2】 [Table 2]
【0016】表1に示した参考方法では、脱塩素反応が
起こり塩素数の多いダイオキシン類の低塩素化が進み、
逆に塩素数の少ないダイオキシン類の増加が見られたの
に対し、二酸化マンガン触媒とオゾンとを組み合わせた
本発明では、表2に示した通り、高塩素数および低塩素
数の全てのダイオキシン類について低下する傾向が認め
られ、効果的な除去が行われることが確認された。In the reference method shown in Table 1, a dechlorination reaction occurs, and dioxins having a large number of chlorines are reduced in chlorination,
Conversely, dioxins with a low chlorine number increased, while manganese dioxide catalyst and ozone were combined.
In the present invention, as shown in Table 2 , high chlorine number and low chlorine
All the dioxins in the number tended to decrease, confirming that effective removal was performed.
【0017】次に、全ダイオキシンが940pg/Lである
原水を参考方法、本発明、オゾンのみによる処理、紫外
線とオゾンによる処理の4通りの方法で処理し、その結
果を表3にまとめた。このデータから明らかなように、
特に本発明ではオゾン処理法や紫外線+オゾン処理法に
比較して、高い除去率を得ることができる。Next, raw water having a total dioxin content of 940 pg / L was treated by the reference method , the present invention, treatment with only ozone, and treatment with ultraviolet light and ozone, and the results are summarized in Table 3. As evident from this data,
In particular, in the present invention, a higher removal rate can be obtained as compared with the ozone treatment method or the ultraviolet ray + ozone treatment method.
【0018】[0018]
【表3】 [Table 3]
【0019】[0019]
【発明の効果】以上に説明したように、本発明のダイオ
キシン含有排水の処理方法によれば、排水中の高塩素数
および低塩素数の全てのダイオキシンを、効果的にかつ
経済的に分解除去することができる。As described above, according to the present invention, diode of the present invention
According to the treatment method for wastewater containing xin , high chlorine content in wastewater
And all dioxins having a low chlorine number can be effectively and economically decomposed and removed.
【図1】参考方法を示す断面図である。FIG. 1 is a sectional view showing a reference method .
【図2】本発明の実施形態を示す断面図である。FIG. 2 is a sectional view showing an embodiment of the present invention.
1 反応槽、2 触媒充填層、3 排水供給ライン、4
処理水ライン、5オゾンガス散気装置、6 オゾン供
給ライン、7 排オゾン処理装置1 reaction tank, 2 catalyst packed bed, 3 drainage supply line, 4
Treated water line, 5 ozone gas diffuser, 6 ozone supply line, 7 waste ozone treatment device
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6,DB名) C02F 1/78 B01J 23/34 C02F 1/58 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 6 , DB name) C02F 1/78 B01J 23/34 C02F 1/58
Claims (2)
粒状の二酸化マンガン触媒を充填した反応塔に通水しつ
つ、排水中に共存するCODの3倍(重量比)以上のオ
ゾンを供給することにより、排水中の高塩素数のダイオ
キシンのみならず低塩素数のダイオキシンから塩素を脱
離分解させることを特徴とするダイオキシン含有排水の
処理方法。A wastewater containing dioxin is powdered,
Passing water quality in a reaction tower filled with particulate manganese dioxide catalyst
One more than 3 times (weight ratio) of COD coexisting in wastewater
By supplying zon, high chlorine count in wastewater
A method for treating dioxin- containing wastewater, comprising desorbing and decomposing chlorine from dioxins having a low chlorine number as well as toxins .
無機材料、あるいは高分子樹脂等の有機材料に担持させ
た形状で用いる請求項1に記載のダイオキシン含有排水
の処理方法。 2. The method for treating dioxin- containing wastewater according to claim 1, wherein the manganese dioxide catalyst is used in a form supported by an inorganic material such as ceramics or an organic material such as a polymer resin.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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JP8060798A JP2923494B1 (en) | 1998-03-27 | 1998-03-27 | Treatment method for dioxin-containing wastewater |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8060798A JP2923494B1 (en) | 1998-03-27 | 1998-03-27 | Treatment method for dioxin-containing wastewater |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2923494B1 true JP2923494B1 (en) | 1999-07-26 |
JPH11277082A JPH11277082A (en) | 1999-10-12 |
Family
ID=13723027
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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JP8060798A Expired - Lifetime JP2923494B1 (en) | 1998-03-27 | 1998-03-27 | Treatment method for dioxin-containing wastewater |
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Country | Link |
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JP (1) | JP2923494B1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2006263650A (en) * | 2005-03-25 | 2006-10-05 | Ngk Insulators Ltd | Ceramic membrane purified water making equipment and its operation method |
-
1998
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JPH11277082A (en) | 1999-10-12 |
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